Hepatocytes make up 70-80% of the mass of the liver. These cells are involved in protein synthesis, protein storage and transformation of carbohydrates, synthesis of cholesterol, bile salts and phospholipids, and detoxification, modification and excretion of exogenous and endogenous substances. The hepatocyte also initiates the formation and secretion of bile.
Hepatocytes have the ability to metabolize, detoxify, and inactivate exogenous compounds (those acquired from outside the bidy) such as drugs and insecticides, and endogenous compounds (made within the body) such as steroids. The drainage of the intestinal venous blood into the liver requires efficient detoxification of miscellaneous absorbed substances to maintain homeostasis and protect the body against ingested toxins. One of the detoxifying functions of hepatocytes is to modify ammonia into urea for excretion.